ALROSA said that pre preliminary results of an experiment carried out at the northwestern area of the Zapolyarnaya pipe indicate that the Verkhne-Munskoye deposit, of which it is a part, can become one of the richest of the Company’s deposits in terms of large diamonds.

The Verkhne-Munskoye diamond deposit, where presently four kimberlite pipes are being explored including Zapolyarnaya, is today the largest investment project of ALROSA. Work at the project was officially launched in October 2018.

The experiment, aimed at clarifying the diamond-bearing capacity of the pipe, took place on March 11-15. During that period, the processing plant N12 in the town of Udachny processed about 100 thousand tons of ore supplied exclusively from the northwestern part of the Zapolyarnaya pipe.

In the five days, 239 diamonds, or more than 3.5% of the total extracted were large diamonds over 8 carats, indicating that the diamond grades were higher than expected. The overall results will be used to determine the expected colour characteristics of diamonds, the grades and the cost of one carat in this particular part of the pipe.

“The experiment showed once again that the Verkhne-Munskoye deposit is rich in large crystals. In 5 days, we extracted 239 large (over 8 carats) diamonds from the Zapolyarnaya pipe, or more than 3.5% of the number of diamonds extracted during the experiment. This is a very significant indicator,” Andrey Cherepnov, ALROSA Chief Engineer, said.

ALROSA said that there were two gem-quality stones weighing 51.15 and 70.67 carats among the extracted large diamonds. In addition, four large diamonds of lower quality were mined; the largest one weighing 268 carats.

All the crystals have now been sent to ALROSA’s Diamond Sorting Center in the town of Mirny, where the main quality characteristics of these stones will be determined and their assessment made.

Earlier, two large high-quality diamonds, weighing 51.49 and 98.8 carats, were mined at the Verkhne-Munskoye deposit.

Pic caption: Some of the large diamonds recovered at the Verkhne-Munskoye deposit

Pic courtesy: ALROSA